Auxiliary-locomotive propulsion unit



April 23, 1929. R. s. A. DOUGHERTY ET AL 1,710,354

AUXILIARY LOCOMOTIVE POPULSION UNIT I Filed Aug. 21, 1926 2 INVENTQRS h. 0 MI BY w %TTORNEY II Y.

Patented Apr. 23,

wan-STAT S PAT NT OFFICE.

noBEn'r s A. nouennarmpr BETHLEHEM, PENNSYLVANIA, AND JOHN A. mcenEw. or ALBANY, NEW YORK, AssIsNons :ro BETHLEHEM STEEL comrANY;

nuxrnmnx-rocomo'rrvn rRorUnsxoN UNIT.

Applicationtled August 21, 1926. Serial No. 130,606.

Our invention relates to auxiliary locomotive propulsion units and particularly to pro- 7 pulsion units. of the type which may be operatively connected to or disconnected from 5 an axle of a railway vehicle.

' Heretofore, it has been proposed to use a train of gears to secure operative relation v between the propulsion unit and the driven axle and to provide an intermediary mechanism serving to place such gears in meshed .or demeshed relation, as desired. Suchin termediary mechanism has been utilized when operated by air or in other cases'by steam and in certain-cases, the steam has been a part ofthe main supply of the steam that operates the propulsion unit. However, with such intermediary mechanism, it is extremely diflicultto synchronize its operation with .the operation of the propulsion unit and unless the meshing of the gears'is effected within certain speed limits of the propulsion unit,relative to the driven axle speed, the gcars'are subjected to considerable shock when they are placed in meshed engagement. It is, therefore, the object of our invention to entirely obviate the use of such intermediary mechanism and to provide a means adapted to operatively connect the propulsion unit to the driven axle solely by the initial turning pulsion unit.

Another object of our invention is the provision of a novel and simple means adapted to cooperate with a railway vehicle propulsion unit to automaticallycause the latter to be operatively connected to a driven axlebf such vehicle, during the initial op eration of the propulsion unit. Another object of our invention is to pro vide a driving connection between an auxiliary locomotive comprising a train of" gears adapted to be maintained in operative meshing relation vsolely by 'the resultant of the working forcesset up between the teeth of the respective gears and which is automatically demeshed when such force is decreased. Broadly stated, our invention comprises an auxihary locomotive propulsion unit adapted to be mounted on a railway vehicle and normally constrained from engagement over effort of the pro and having a drive shaft to which is fixedly 'the axle gear and thus produce a driving corlmection between said drive shaft and the ax e.

Other novel features will be more fully understood from the following description and claims taken with the drawings, in which:

Flg. 1 is a longitudinal cross section through an auxiliary locomotive embodying our invention;

Fig. 2 is across section through the entrainment gearing, somewhat enlarged;

51g. 3 is a partial plan view of Fig. 1; an

Fig.4 is a similar View to Fig. 2 embodying a modified form of abutment member.

Referringto the drawings more in detail, 10 designates generally an auxiliary locomotlve propulsion unit of a type similar to that described and shown in Letters Patent No. 1,412,250 granted to John A. McGrew and James T. Loree under date of April 11, 1922.

As fully described in the aforesaid patent, the frame 11 of the propulsion unit. is 85 mounted on the load bearing axles 12 and 13 of a railway vehicle, preferably the locomotive tender. As shown and described in said patent, the engine 14 is supplied with steam from the locomotive boiler by the pipe 15 and drives a crank shaft mounted in suitable bearings upon theframe.

The aforementioned crank shaft is provided with adriving toothed gear 16, the axle 13 is provided with a driven toothed gear 17 and said gears are disposed in alignment with each other. An idler gear 18 is constantly in mesh with the driving gear 16 and it is maintained in this relation by the idler support 19. The latter is capable of 100 angular movement with respect to the axis of the driving gear so that the idler gear 18 has a planetary movement about same when it moves into and out of mesh with the driven brace member of the frame. The end of the rod 20' is threaded and provided with an adjustable collar 21. Inter-posed between the latter and the frame and surrounding the rod 20'. is a coil spring 22 which serves normally to bias the support 19 and hold the idler gear out of mesh with the driven gear.

\ that the member 23 may readily tilt as hereinafter set forth. The member 23 has the end thereof remote from the idler gear weighted, as indicated at 27, in order .to normally biasthe portion 26 towards the teeth of the idler gear.

When the driving gear 16 is turned in the direction of the arrow shown in Fig. 2, the rotation idler gear 16 from rotation aboutits own axis is resisted due to engagement of the abutment portions 25 or 26 between the teeth thereof. Consequently the reaction between the support 19 and the idler gear 18 causes a movement of the latter towards the driven gear; and, while movement takes place in thisdirection, the abutment member 23 tilts about its axis 24. In consequence of this, the portions 26 and 25 act in succession on the idler gear 18 and such portions are preferably not fully disengaged from the idler gear until the latter is almost at the point of meshing with the driven gear.

From the arrangement of it will be apparent that it is only necessary for the tips of the teeth of the idler gear to first engage between the tips of the teeth of the driven gear and that thereafter the relative arrangement of the gears and the direction of rotation thereof are such as to cause the idler gear to be drawn completely into mesh with the driven gear due to the resultant of the Working forces set up between the teeth of the respective gears. Although we prefer to have the idler gear engaged by the abutment member until the idler gear is almost in engagement with the driven gear or even initially engaged therewith, it 'will be apparent that disengagement of the abutment, member might take place before the idler gear has moved into close proximity to the driven gear for the reason that the tumbler gear and its support are moving in an entraining direction and the inertia of the parts is suflicient to overcome the spring 22 and to secure enmeshment of the idler gear with the driven gear 17.

gearing shown,

when the latter assumes In 4 we show a modified type of abutment member 23' having a tooth or abutment portion 25' formed thereon which normally engages the idler gear. With this type of abutment member the rotation of the idler gear about its own axis is resisted and the support 19"and the, idler gear are given an initial movement towards the driven gear and thereafter the inertia of the parts secures the enmeshment of the idler with the driven gear.

The abutment member 23' I is I normally biased towards the idler gear by reason of its centerof gravity being at the same side of the pivot 24' as such gear. The biasing of the abutment member secures angular movement thereof while the idler gear is being'ent rained and such angular movement is limited by a stop in the form of a pin 30 extending laterally from the abutment-member which is adapted to engage the frame and thereby limit the movement of the abutment member towards the idler gear.

As shown in F igs.2 and 3, abutment member 23 is provided with shoulders 28 which are adapted to engage portion 29 of the frame, engagement thereof limiting the downward movement of member 23 as the idler gear goes into mesh with the driven gear, or just before doing so.

Referring to Fig. 2, the abutment member 23 will be maintained out of contact with the idler gear and the portion;26 thereof will occupy such a position that, when the idler gear and its support '19 move in a disentraining direction, such portion will be initially engaged by the tumbler gear and the abutment member will be tilted about its axis 24 until both between the teeth of the idler gear.

Referring now to Fig. 4, when the idler gear and itssupport 19 move in a disentraining direction, the periphery of the gear engages the inclined surface 31 of the abutment member 23 and causes the latter to tilt about its axis 24: and thus allow the idler gear to return to its normal disentrained position. If by chance the abutment portion 25 does not register with a space between the teeth of the idler gear,

its rearward position, the abutment member rests on the tip of the tooth, then at the subsequent operation of the driving gear the initial move mentof the latter causes rotation of the while power is being transmitted from the engine unit to the drlven gear the idler gear is maintained in mesh withthe latter gear,

solely by the resultant of the working forces portions 25 and 26 are positioned idler set up between the teeth of the respective gears. When the engine 14 is shut off power is no longer transmitted therefrom to the driven gear and the working forces between the teeth of the gear is relieved to such an extent that the spring 22 causes the discotrainment of the idler gear from the driven gear. \Vhen the speed of the rotation of the axle carrying the driven gear exceeds a. predetermined amount by virtue of the speed of the train being propelled at-higher speeds by the main propulsion unit, theworking forces between the teeth of the gears reduces sufiiciently so that the spring 22 acts to disentrain the idler gear from the driven gear, and thus prevents the engine 14 being driven by the main propulsion unit through the medium of the axle carrying the gear 17 which might otherwise occur to cause the engine 14 to function as a compressor with an abnormally high piston speed to the detriment of the engine. I

' It will be seen from the foregoing that we have devised a novel and simple device for automatically entraining an auxiliary locomotive propulsion unit with a normally Having thus described the invention what we claim as new and desire to secure by Letters Patent is:

1. In ail-auxiliary locomotive propulsion unit, the combination of a driving gear, a driven gear, an idler gear constantly meshingwith the driving gear and movable towards the driven gear, a fixed pivot, an abutment member mounted on said pivot and normally engaging a toot-h of the idler gear, 'means biasing said abutment member towards the idler gear, and means limiting the movement of said abutment member'towards'the idler gear. I

2. In an auxiliary locomotive propulsion unit, the combination of an engine having a drive shaft, a driving gear fixedly mounted on said shaft, an axle carrying a driven gear, an idler gear constantly meshing with the driving gear, a support for said idler gear rotatively mounted on a bearing coaxial with said shaft, a pivot fixed relative to said support, an abutment member mounted on said pivot and normally engaging a tooth formed on the idler gear, means to bias said member towards the idler gear, means to limit the movement of said member towards the idler gear, and means constraining said idler gear into engagement with said abutment member.

In testimony whereof I hereunto aflix my signature.

signature.

JOHN A. MCGREW. 

